(1) Field of the Invention
This invention relates to apparatus for recording onto a magnetic recording medium and for playing back the record so as to verify the recorded signal to enable different processing of media containing verified and non-verified records. This invention also relates to apparatus for dispensing labels such as may contain a magnetic recording.
(2) Description of the Prior Art
Magnetic recording apparatus including a transport mechanism, a recording head for magnetically encoding a magnetic recording medium transported by the mechanism past the head, a playback head positioned to scan the magnetic record medium after it has been encoded, i.e., trailing the record head, and logic circuits for verifying the encoded record are previously known. One such apparatus is designed for use with a magnetic disk-pack and enables a limited number of defects on a disk-pack to be located such that no signals are thereafter recorded at those locations.
In other magnetic recording apparatus such as instrumentation recorders, a playback head may be enabled during the recording process to verify the compliance of the recorded signal with certain prerequisites such as frequency response, harmonic distortion, signal-to-noise ratio, bias cross feed, cross talk and the like. In such recorders, if the recorded signal fails to meet the desired levels, the recording parameters are then readjusted. In all such systems, the purpose of the verification operation is to enable the apparatus to cope with various types of defects, be they in the magnetic media itself or in the quality of the incoming data signals.
Inasmuch as another aspect of the present invention is also directed to dispensing magnetically encoded labels, prior art relating to dispensing apparatus is also believed relevant. For example, apparatus for automatically dispensing tickets (in some respects at least analogous to labels) are known to be used in systems for controlling access to parking lots and ramps. In a typical such system, one driving across a pressure switch at the entrance to the facility causes a ticket to be time-stamped and presented at a dispenser slot. Removal of the ticket automatically causes another ticket to be advanced. Such systems are not known to utilize labels including a magnetic recording material nor to provide any capability of recording thereon.